JP6468162B2 - Obstacle notification device - Google Patents

Description

  The present invention relates to an obstacle notification device that notifies a driver of information about obstacles existing around a vehicle.

  2. Description of the Related Art Conventionally, a device (hereinafter referred to as an obstacle notification device) that detects an obstacle existing in the traveling direction of a vehicle by transmitting and receiving a predetermined exploration wave and notifies the driver of the presence of the obstacle is known.

  For example, the obstacle notification device disclosed in Patent Document 1 detects the distance between an obstacle present in the traveling direction of the vehicle and the distance of the vehicle using an ultrasonic sensor that transmits and receives an ultrasonic pulse as an exploration wave. When the distance between the detected obstacle and the vehicle is less than a predetermined threshold, the driver is notified of the presence of the obstacle by outputting an alarm sound or the like. Here, the obstacle refers to an object among the various objects whose presence should be notified to the driver. For example, an object having a size that prevents the vehicle from traveling may be assumed as an obstacle.

  In such an obstacle notification device, a millimeter wave using a millimeter wave (including a quasi-millimeter wave) as an exploration wave in addition to an ultrasonic sensor as a sensor for detecting an obstacle (hereinafter referred to as an obstacle sensor). Various sensors such as radar are used.

  The obstacle sensor transmits an exploration wave and receives a reflected wave reflected by an object existing within the reach of the exploration wave. Then, when the received intensity of the received reflected wave exceeds a preset threshold for determining that there is an obstacle (hereinafter, a determination threshold), it is determined that an obstacle is present. Determining that there is an obstacle corresponds to detecting the obstacle.

  Note that the determination of whether or not an obstacle exists may be performed by the obstacle sensor itself, or the electronic control device existing outside the obstacle sensor acquires information indicating the reception intensity from the obstacle sensor. It may be carried out by doing. For convenience, the functional module that is included in the obstacle sensor or the electronic control device and determines whether or not an obstacle exists is referred to as an obstacle determination unit. The obstacle determination unit may be realized as hardware using one or a plurality of ICs, or may be realized by the CPU executing predetermined software.

JP-A-2015-135301

  The exploration wave transmitted by the obstacle sensor is reflected not only by the obstacle but also by an object (hereinafter referred to as a noise element) that does not need to be reported to the driver, such as a road surface, and returns to the obstacle sensor. For this reason, if the determination threshold is made too small, the possibility of an erroneous determination that an obstacle exists due to a reflected wave from a noise element increases. On the other hand, if the determination threshold is set too high, there is a risk that detection of an object (that is, an obstacle) that should originally be notified to the driver is delayed or cannot be detected.

  Therefore, in the conventional obstacle notification device, a value assumed as a reception intensity of a reflected wave from a road surface with a uniform inclination (hereinafter referred to as a uniform road surface) is specified by a test or the like, and a determination threshold value is uniform. The value was set so that the reflected wave from the road surface would not easily exceed. According to such an aspect, it is possible to reduce a possibility that the obstacle determination unit erroneously determines that an obstacle exists due to a reflected wave from the uniform road surface in a situation where the vehicle exists on the uniform road surface.

  However, the environment in which the vehicle travels is not limited to a uniform road surface. On the road where the vehicle actually travels, there is a point where the inclination degree changes. If the vehicle is present on a substantially horizontal road before the uphill starts, the obstacle determination unit may erroneously determine that the uphill road surface is an obstacle. This is because the uphill road surface is raised with respect to the road surface on which the vehicle exists, and thus the exploration waves are easily reflected toward the vehicle.

  Further, not only a change in the slope of the road but also a road surface irregularity corresponding to the roughness of the pavement, a minute step on the road, rain, snow, etc. can cause an erroneous detection of an obstacle. If the obstacle sensor erroneously detects the object, an alarm for notifying the presence of the obstacle is performed based on the erroneous detection, and there is a possibility that the passenger feels uncomfortable or uncomfortable.

  The present invention has been made on the basis of this circumstance, and the object of the present invention is to suppress the possibility of performing unnecessary notification in an obstacle notification device that notifies the driver of the presence of an obstacle. The object is to provide an obstacle notification device.

  A first invention for achieving the object is mounted on a vehicle, transmits a search wave in the traveling direction of the vehicle, and receives a reflected wave returned by the search wave reflected by an object. The search result acquisition unit (F4) that sequentially acquires the reception intensity of the reflected wave received by the search wave transmission / reception device and the reception intensity of the reflected wave acquired by the search result acquisition unit are used to indicate the presence to the vehicle driver. Based on the obstacle determination unit (F5) that determines whether or not an obstacle to be notified exists in the traveling direction of the vehicle, and that the obstacle determination unit determines that an obstacle exists. Then, a notification processing unit (F6) that performs notification processing for notifying the driver of the presence of the obstacle, and a camera that includes the arrival range of the exploration wave transmitted by the exploration wave transmission / reception device within the photographing range. image data As an element that can reflect the exploration wave by analyzing the image data acquisition unit (F1) to be acquired and the image data acquired by the image data acquisition unit, and that does not need to be notified to the driver A noise element detection unit (F2) that detects the presence of a noise element that is a preset element, and the obstacle determination unit detects noise when the noise element detection unit detects the noise element. It is characterized in that it is determined whether or not an obstacle exists by using a condition that is less likely to be satisfied than a condition used when the element detection unit has not detected a noise element.

  In the above configuration, the noise element detection unit detects the noise element by analyzing the image data of the camera. When the noise element is detected by the noise element detection unit, the obstacle determination unit uses the condition that is less likely to be satisfied than the condition used when the noise element is not detected. It is determined whether or not.

  That is, according to the above configuration, when a noise element is detected by the noise element detection unit, a condition that is less likely to be satisfied is applied as a condition for the presence of an obstacle. Therefore, it is difficult to determine that an obstacle exists. As a result, it is possible to reduce the risk of unnecessary notification being performed.

  A second invention for achieving the object is an exploration wave transmission / reception which is mounted on a vehicle and transmits a search wave in the traveling direction of the vehicle and receives the reflected wave reflected by the object. A search result acquisition unit (F4) that sequentially acquires the reception intensity of the reflected wave received by the device, a default threshold that is set in advance to determine that there is an obstacle that should be notified to the driver of the vehicle, An obstacle determination unit (F5) that compares the reception intensity of the reflected wave acquired by the exploration result acquisition unit and determines that an obstacle exists when the reflected wave exceeds the default threshold, and an obstacle determination Based on the fact that the obstacle is determined to be present by the unit, the notification processing unit (F6) that performs notification processing for notifying the driver of the presence of the obstacle, and the exploration wave transmission / reception device An image data acquisition unit (F1) that acquires image data captured by a camera that includes the reach of the exploration wave to be captured in the imaging range, and the image data acquired by the image data acquisition unit can be analyzed to reflect the exploration wave A noise element detection unit (F2) that detects the presence of a noise element that is an element that is preset as an element that does not need to be notified to the driver of the vehicle; When detecting the element, the output for adjusting the output level of the exploration wave to a level smaller than the rated level set in advance as the output level used when the noise element detection unit does not detect the noise element A search wave transmitting / receiving device that transmits the search wave at an output level set by the output level adjustment unit.

  According to the above configuration, the exploration wave transmission / reception device transmits the exploration wave at a predetermined rated level when the noise element is not detected by the noise element detection unit, while the noise element is detected. Transmits the exploration wave at an output level smaller than the rated level.

  Naturally, if the output level is reduced, the reception intensity of the reflected wave from the noise element is also reduced. Therefore, it is possible to reduce the risk of erroneous determination that an obstacle exists by receiving a reflected wave from a noise element. As a result, the risk of performing unnecessary notification can be reduced.

  In addition, the code | symbol in the parenthesis described in the claim shows the correspondence with the specific means as described in embodiment mentioned later as one aspect, Comprising: The technical scope of this invention is limited is not.

It is a block diagram which shows an example of a structure of the obstacle alerting | reporting system 100 which concerns on 1st Embodiment. It is a block diagram which shows an example of a structure of periphery monitoring ECU1 in 1st Embodiment. It is a figure for demonstrating default threshold value ThD (T). It is a figure for demonstrating a noise influence time slot | zone. It is a figure for demonstrating a noise influence time slot | zone. It is a flowchart for demonstrating the rough action | operation of periphery monitoring ECU1. It is a figure for demonstrating the action | operation of the obstruction determination part F5. It is a figure for demonstrating the action | operation of the obstruction determination part F5. It is a figure for demonstrating an assumption structure. It is a figure for demonstrating the action | operation of the obstruction determination part F5 in the modification 1. FIG. It is a figure for demonstrating the action | operation of the obstruction determination part F5 in the modification 2. FIG. It is a block diagram which shows an example of a schematic structure of periphery monitoring ECU1 in 2nd Embodiment. It is a flowchart for demonstrating the rough action | operation of periphery monitoring ECU1. It is a block diagram which shows an example of a structure of periphery monitoring ECU1 in 3rd Embodiment. It is a flowchart for demonstrating the rough action | operation of periphery monitoring ECU1.

[First Embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the drawings. An obstacle notification system 100 shown in FIG. 1 is mounted on a vehicle and includes a periphery monitoring ECU 1, an ultrasonic sensor 2, a camera 3, and a notification device 4. Hereinafter, a vehicle equipped with the obstacle notification system 100 is referred to as a host vehicle. Note that ECU is an abbreviation for Electronic Control Unit.

  The obstacle notification system 100 is a system for notifying the driver of obstacles existing in the traveling direction of the host vehicle. Here, as an example, the obstacle notification system 100 notifies the driver of an obstacle existing ahead of the host vehicle when the host vehicle is moving forward. Of course, as another aspect, the obstacle notification system 100 may notify the driver of an obstacle existing behind the host vehicle when the host vehicle is moving backward. In that case, what is necessary is just to adjust the installation position, installation posture, etc. of the ultrasonic sensor 2 and the camera 3 so that the driver can be notified of obstacles existing behind the host vehicle. In addition, an obstruction here is an object which should alert | report the presence to a driver, for example, points out the object which has a magnitude | size which prevents the advance of the own vehicle. Hereinafter, the configuration of the obstacle notification system 100 in the present embodiment will be described.

<Schematic configuration of obstacle notification system>
The periphery monitoring ECU 1 is connected to each of the ultrasonic sensor 2, the camera 3, and the notification device 4 through a local network (hereinafter, LAN: Local Area Network) 5 built in the vehicle so as to be able to communicate with each other. . The periphery monitoring ECU 1 controls the operation of the entire obstacle notification system 100. Details of the periphery monitoring ECU 1 will be described later.

  The ultrasonic sensor 2 transmits an ultrasonic pulse as an exploration wave at a predetermined transmission cycle, and receives a reflected wave returned by the transmitted ultrasonic pulse reflected by an object existing outside the host vehicle. And the signal which shows the signal strength of the received reflected wave is sequentially output to periphery monitoring ECU1. The ultrasonic sensor 2 corresponds to the exploration wave transmitter / receiver described in the claims.

  The transmission of the ultrasonic pulse and the reception of the reflected wave may be realized using one oscillation element. Of course, as another aspect, one or a plurality of reception oscillation elements may be provided separately from the transmission oscillation elements. The transmission cycle may be several hundred milliseconds, for example. Here, as an example, the transmission cycle is 100 milliseconds.

  The ultrasonic sensor 2 only needs to be installed at a position (for example, a front bumper) appropriately designed in the host vehicle so as to transmit an ultrasonic pulse in front of the host vehicle. Here, the front includes not only the front direction of the vehicle but also a diagonal front. The front direction is a direction from the rear end of the host vehicle to the front end of the host vehicle.

  Here, as an example, the ultrasonic sensor 2 is provided such that the direction serving as the center of directivity coincides with the front direction of the host vehicle. As another aspect, the center direction of the directivity of the ultrasonic sensor 2 may be installed so as to be inclined by about 30 ° in the vehicle width direction from the vehicle front direction.

  The directivity of the ultrasonic sensor 2 and the intensity of the ultrasonic pulse to be transmitted may be adjusted so as to form a desired detection area. The detection area is a range in which an obstacle can be detected. A range in which the ultrasonic sensor 2 can receive a reflected wave from an object of a predetermined size with a predetermined reception intensity corresponds to a detection area. This detection area corresponds to the reachable range described in the claims. A plurality of ultrasonic sensors 2 may be provided.

  The camera 3 is an optical camera. For example, the camera 3 may be realized using a CMOS camera, a CCD camera, or the like. The camera 3 is installed in the vicinity of the windshield upper end (for example, in the vicinity of a room mirror) so as to photograph a predetermined range in front of the host vehicle. For the sake of convenience, the range captured by the camera 3 is hereinafter also referred to as a shooting range. Data of an image captured by the camera 3 (hereinafter referred to as image data) is sequentially provided to the periphery monitoring ECU 1.

  In addition, the installation position of the camera 3 should just be designed suitably, and is not restricted to the vicinity of a room mirror. The camera 3 should just be attached in the position which does not block the driver | operator's visual field with respect to the vehicle front. However, it is assumed that the camera 3 is installed so that the photographing range includes the detection area of the ultrasonic sensor 2.

  In the present embodiment, the camera 3 is an optical camera as an example, but as another aspect, the camera 3 may be an infrared camera, a near infrared camera, or the like. Furthermore, the camera 3 may be a stereo camera.

  The notification device 4 is a device that outputs information indicating that an obstacle is present in the traveling direction of the host vehicle (here, forward) in a manner that can be perceived by the driver, based on an instruction from the surrounding monitoring ECU 1. As the notification device 4, a display, an indicator such as an LED, a speaker, a vibrator, or the like can be used.

<Regarding Configuration and Operation of Perimeter Monitoring ECU 1>
The periphery monitoring ECU 1 is configured as a computer, and includes a CPU 11, a RAM 12, a ROM 13, an I / O, and a bus line that connects these configurations. The ROM 13 stores a program (hereinafter referred to as an obstacle notification program) for causing a normal computer to function as the periphery monitoring ECU 1 in the present embodiment.

  The ROM 13 also stores setting data related to the ultrasonic sensor 2 and the camera 3. The setting data related to the ultrasonic sensor 2 is data indicating the installation position and detection area of the ultrasonic sensor 2 in the own vehicle, and the setting data related to the camera 3 is data indicating the installation position of the camera 3 and the imaging range. It is. Further, the ROM 13 also stores a default threshold value that is set in advance as a threshold value that is used to determine whether an obstacle exists based on the reception intensity provided from the ultrasonic sensor 2.

  Note that the obstacle notification program described above may be stored in a non-transoryory tangible storage medium such as a ROM. Executing the obstacle notification program by the CPU 11 corresponds to executing a method corresponding to the obstacle notification program.

  As shown in FIG. 2, the periphery monitoring ECU 1 executes an obstacle notification program as described above, and as shown in FIG. 2, the image data acquisition unit F1, the image recognition unit F2, the influence identification unit F3, and the search result acquisition unit F4. The obstacle determination unit F5 and the notification processing unit F6 are provided. The obstacle determination unit F5 includes a distance specifying unit F51 as a finer functional block. Note that some or all of the functional blocks provided in the periphery monitoring ECU 1 may be realized as hardware using one or a plurality of ICs. This periphery monitoring ECU 1 corresponds to the obstacle notification device described in the claims.

  The threshold storage unit M1 illustrated in FIG. 2 is an area that stores data indicating the default threshold value read from the ROM 13 among the storage areas included in the RAM 12. In the present embodiment, as shown in FIG. 3, the default threshold is set to a value corresponding to the elapsed time from the start of transmission of the ultrasonic pulse.

  Specifically, the default threshold value from the start of transmission of an ultrasonic pulse to the elapse of a predetermined reverberation convergence time Tx is that the transmitted ultrasonic pulse itself and the reverberation of the transmitted ultrasonic pulse are determined from the object. Is set to a sufficiently large value so as not to be erroneously detected as a reflected wave.

  Here, the reverberation corresponds to an ultrasonic wave generated by vibration from the completion of the transmission of the ultrasonic pulse until the oscillation element stops. The reverberation gradually attenuates. The time from the start of transmission of an ultrasonic pulse until the reverberation converges, that is, the reverberation convergence time Tx is specified by an actual test, simulation, or the like. A broken line L1 in FIG. 3 indicates the transmitted ultrasonic pulse itself and the reception intensity corresponding to the reverberation of the transmitted ultrasonic pulse.

  Further, the default threshold value after the time point when the reverberation convergence time Tx elapses after the transmission of the ultrasonic pulse is started is set to a value Pa assumed as the reception intensity of the reflected wave from the uniform road surface, and a predetermined margin Pb is set. A uniform road surface assumed value Pc which is an added value is used. The uniform road surface here is a road surface in which the degree of unevenness of the road surface corresponding to the roughness of the pavement is within a predetermined allowable range, and the road surface inclination degree (in other words, the gradient) is uniform. Point to.

  The reception intensity Pa of the reflected wave from the uniform road surface may be specified by an actual test or simulation. The predetermined margin Pb is a value for preventing the obstacle determination unit F5 from erroneously determining that an obstacle exists due to a reflected wave from the road surface of the actual road. The margin Pb is in consideration of the difference between the unevenness level of the road surface assumed as a uniform road surface and the actual road surface unevenness degree, nonuniformity of the road surface gradient on the actual road (in other words, the degree of curvature), and the like. What is necessary is just to determine suitably.

  The default threshold value may be expressed as a function with the elapsed time T from the start of transmission of the ultrasonic pulse as a variable, or may be expressed in a table format. The data indicating the default threshold may be expressed in a format in which the default threshold corresponding to the elapsed time T is uniquely determined. Here, as an example, it is assumed that a function indicating a correspondence relationship between an elapsed time T from the start of transmission of an ultrasonic pulse and a default threshold is expressed as a program. For convenience, the default threshold value corresponding to a certain elapsed time T is hereinafter also referred to as default threshold ThD (T).

  Next, various functional blocks will be described. The image data acquisition unit F1 sequentially acquires image data from the camera 3. The image recognizing unit F2 analyzes the image data acquired by the image data acquiring unit F1 to change the road gradient change point (hereinafter referred to as the gradient change point) or the road surface after the gradient change point with respect to the currently running road surface. Recognize relative slopes, road conditions, objects on the road, weather conditions, etc.

  Here, the road surface state includes, for example, whether or not the road surface is paved, the degree of unevenness of the road surface, whether or not the vehicle is wet, whether or not there is a puddle, and whether or not there is snow. The weather condition means whether it is raining, snowing, hail or the like.

  A known technique may be used as a method of detecting the various elements described above from the image data captured by the camera 3. The detection of the gradient change point and the estimation of the relative gradient of the road surface after the gradient change point with respect to the currently running road surface may be performed using, for example, the technique disclosed in Japanese Patent Application Laid-Open No. 2009-133830.

  For example, the disclosure in JP-T-2015-510119 may be used to specify the degree of unevenness on the road surface. Whether the road surface is paved, whether it is flooded, whether there is a puddle, whether there is snow, etc. may be implemented with the aid of the technology disclosed in Japanese Patent No. 5720380, for example. Furthermore, what is necessary is just to implement the specification of a weather condition, for example using the technique of patent 4505509.

  Further, the image recognition unit F2 may detect an object (hereinafter referred to as a detection target) preset as a detection target by performing pattern matching processing on the image data. What is necessary is just to design a detection target suitably. For example, walls, guardrails, utility poles, people, road cones, curbs, wheel stops, etc. may be registered as detection objects.

  By the way, in various objects and environments detected by the image recognition unit F2 from image data, elements that can reflect an ultrasonic pulse and do not need to be notified to the driver of the vehicle (hereinafter referred to as the elements). Noise element). The image recognition unit F2 also determines whether there is a noise element in the detection area of the ultrasonic sensor 2 (in other words, detection of the noise element).

  Noise elements include, for example, road surfaces where the degree of unevenness exceeds a predetermined tolerance, a slope increase point that is a slope change point where the slope increases, a road that extends from the slope increase point, a high road Steps and falling objects whose length is less than a predetermined reference value (for example, several centimeters), flooded roads, puddles, snow accumulation, rainfall, snowfall, rainfall, and the like.

  Of the elements that can be recognized by the image recognition unit F2, elements that are noise elements may be registered in advance. In the present embodiment, the image recognition unit F2 detects an element other than the noise element, but is not limited thereto. The image recognition unit F2 only needs to detect at least a noise element. Further, it is not necessary to have a configuration capable of detecting all the above-described noise elements as noise elements. It is sufficient that the configuration is such that an element of a type defined as a noise element can be detected as appropriate. The image recognition unit F2 corresponds to the noise element detection unit described in the claims.

  When detecting the noise element, the image recognition unit F2 specifies the area where the noise element exists in the detection area of the ultrasonic sensor 2 and specifies the distance from the ultrasonic sensor 2 to the noise element. .

  The distance between the noise element and the ultrasonic sensor 2 may be calculated as follows, for example. First, the relative position of the noise element with respect to the host vehicle is specified based on the position of the noise element in the image data and the mounting position and shooting range of the camera 3 in the host vehicle. A known technique may be used as a technique for estimating the relative position with respect to the vehicle from the position of the photographed object in the image data photographed by the in-vehicle camera. Then, the distance from the ultrasonic sensor 2 to the noise element is specified based on the mounting position of the ultrasonic sensor 2 in the own vehicle and the relative position of the noise element with respect to the own vehicle.

  When rain or snow is detected as a noise element, it is determined that there is a noise element in the entire detection area of the ultrasonic sensor 2, and the distance from the ultrasonic sensor 2 to the noise element is determined to be zero. good. The image recognizing unit F2 sequentially provides information on the area where the noise element exists and the distance from the ultrasonic sensor 2 to the noise element to the influence specifying unit F3.

  When the image recognition unit F2 detects a noise element in the detection area of the ultrasonic sensor 2, the influence specifying unit F3 returns a reflected wave at the noise element in the elapsed time T from the transmission start timing. The noise influence time zone, which is a time zone that may come, is specified.

  The operation of the influence specifying unit F3 will be described with reference to FIG. FIG. 4 shows an operation when the image recognition unit F2 detects a gradient increase point at a point at a distance D1 from the ultrasonic sensor 2 as an example. 4A conceptually represents the distance between the gradient increase point detected by the image recognition unit F2 and the ultrasonic sensor 2. FIG.

  In such a case, the influence specifying unit F3 first calculates a reciprocating flight time T1, which is a time required for the ultrasonic pulse to reciprocate in the section from the ultrasonic sensor 2 to the gradient increase point, based on the distance D1. The round trip flight time T1 may be a value obtained by dividing the value obtained by doubling the distance D1 by the speed of sound.

  Then, a time zone in which the elapsed time T is equal to or longer than the time T1a obtained by subtracting the predetermined error absorption time Ta from the round trip flight time T1 is set as the noise influence time zone. The error absorption time Ta may be a constant designed in consideration of an error included in the distance D1 from the ultrasonic sensor 2 calculated by the image recognition unit F2 to the gradient increase point.

  As another example, the influence identifying unit F3 when the image recognition unit F2 detects a minute step (hereinafter, a minute step) whose height is less than the reference value at a point where the distance D2 from the ultrasonic sensor 2 is detected. The operation will be described with reference to FIG.

  FIG. 5A conceptually represents a distance D2 between the minute step detected by the image recognition unit F2 and the ultrasonic sensor 2. In such a case, the influence identifying unit F3 reciprocates the ultrasonic pulse from the ultrasonic sensor 2 to the minute step based on the distance D2 from the ultrasonic sensor 2 identified by the image recognition unit F2 and the sound speed. The round-trip flight time T2, which is the time required for, is calculated.

  A time zone determined based on the round-trip flight time T2 is set as a noise-affected time zone corresponding to a minute step. Here, as an example, a noise influence time zone is defined from a time T2a obtained by subtracting the error absorption time Ta from the round trip flight time T2 to a time T2b obtained by adding the error absorption time Ta to the round trip flight time T2.

  In addition, although the aspect which made the noise absorption time period the error absorption time Ta before and after the elapsed time corresponding to round-trip flight time T2 was illustrated here, it is not restricted to this. A parameter (for example, error absorption time Ta) for determining the start time point and end time of the noise influence time for the area where the noise element exists may be appropriately designed. The start time point of the noise influence time zone for the area where the noise element exists may be determined according to the round trip flight time to the area. The end point may be determined depending on the type of the noise element and how far the noise element exists relative to the ultrasonic sensor 2.

  The search result acquisition unit F4 sequentially acquires the reception intensity output from the ultrasonic sensor 2. The exploration result acquisition unit F4 also acquires a transmission start timing that is a timing at which the ultrasonic sensor 2 starts transmitting an ultrasonic pulse.

  The transmission start timing may be notified from the ultrasonic sensor 2. In addition, when the periphery monitoring ECU 1 itself is configured to control the operation of the ultrasonic sensor 2, the transmission start timing of the ultrasonic pulse is notified from the functional block that controls the operation of the ultrasonic sensor 2. good. Furthermore, the exploration result acquisition unit F4 may recognize the timing when the input reception intensity is equal to or greater than a predetermined threshold as the transmission start timing. The threshold value used for specifying the transmission start timing is a value corresponding to the reception intensity observed at the time of transmitting the ultrasonic pulse, and may be a sufficiently large value so as not to be observed as a reflected wave.

  The obstacle determination unit F5 detects an obstacle based on the reception intensity acquired by the search result acquisition unit F4. The operation of the obstacle determination unit F5 differs depending on whether or not the image recognition unit F2 detects a noise element in the detection area of the ultrasonic sensor 2. First, a case where the image recognition unit F2 has not detected a noise element in the detection area of the ultrasonic sensor 2 will be described.

  When the image recognition unit F2 has not detected a noise element in the detection area of the ultrasonic sensor 2, the obstacle determination unit F5 acquires the transmission start timing from the exploration result acquisition unit F4 and progress from the transmission start timing. Time T is measured. Then, when the currently input reception intensity exceeds the default threshold ThD (T) corresponding to the elapsed time T from the transmission start timing, it is determined that there is an obstacle.

  Next, a case where the image recognition unit F2 has not detected a noise element in the detection area of the ultrasonic sensor 2 will be described. Even when the image recognition unit F2 has not detected a noise element in the detection area of the ultrasonic sensor 2, the obstacle determination unit F5 first acquires the transmission start timing from the search result acquisition unit F4, and from the transmission start timing. The elapsed time T is measured.

  And it is determined whether the elapsed time T corresponds to the noise influence time zone which the influence specific | specification part F3 has specified. Here, when the current elapsed time T does not correspond to the noise influence time zone, the presence or absence of an obstacle is determined using a default threshold ThD (T) corresponding to the current elapsed time T.

  On the other hand, when the current elapsed time T corresponds to the noise influence time zone, a threshold (hereinafter referred to as a noise response threshold) larger than the default threshold ThD (T) corresponding to the current elapsed time T is used. Determine whether there is an obstacle. For convenience, the threshold used for determining whether there is an obstacle will be hereinafter referred to as a determination threshold.

  The obstacle corresponding threshold may be dynamically calculated by the obstacle determination unit F5 based on the default threshold, or may be set in advance. When the noise correspondence threshold is set in advance, the set noise correspondence threshold may be stored in the ROM 13 in the same manner as the default threshold.

  In this embodiment, as an example, the obstacle determination unit F5 dynamically generates a noise corresponding threshold ThN (T) corresponding to the elapsed time T based on the default threshold ThD (T) corresponding to the current elapsed time T. It shall be.

  As an example, the noise corresponding threshold ThN (T) corresponding to a certain elapsed time T is a value obtained by multiplying the default threshold ThD (T) corresponding to the elapsed time T by a predetermined coefficient α. The magnification α may be a real number larger than 1. For example, α = 3 here. As another aspect, the noise correspondence threshold ThN (T) may be a value obtained by adding a predetermined value β to the default threshold ThD (T). β may be a positive value.

  The adjustment parameters such as α and β may be adjusted according to the type of noise element detected by the image recognition unit F2. For example, when the detected noise element is an element that is relatively difficult to return a reflected wave, a value (for example, 3) that is smaller than a value (for example, 3) used in the case of an element that is relatively easy to return a reflected wave. 2) may be adopted as α. Whether or not an element easily returns a reflected wave may be defined in advance for each noise element. The same applies to β.

  Then, when the currently input reception intensity exceeds the noise correspondence threshold ThN (T) corresponding to the elapsed time T from the transmission start timing, it is determined that there is an obstacle.

  According to such an aspect, the obstacle determination unit F5 uses the default threshold ThD (T) when the image recognition unit F2 has not detected a noise element in the detection area of the ultrasonic sensor 2. Is detected. On the other hand, when the image recognition unit F2 detects a noise element in the detection area of the ultrasonic sensor 2 and the elapsed time T corresponds to the noise influence time zone, the noise correspondence threshold ThN (T ) To detect obstacles.

  In addition, when detecting an obstacle, the obstacle determination unit F5 specifies the distance between the detected obstacle and the ultrasonic sensor 2. The distance specifying unit F51 included in the obstacle determining unit F5 is a functional block that specifies the distance between the obstacle and the ultrasonic sensor 2. The distance specifying unit F51 specifies the distance from the ultrasonic sensor 2 to the obstacle by multiplying the elapsed time from the transmission start timing to the detection of the obstacle by the sound speed and dividing by 2.

  The notification processing unit F6 cooperates with the notification device 4 to perform processing (hereinafter referred to as notification processing) for notifying the driver of the host vehicle that an obstacle exists in front of the host vehicle. For example, when the notification device 4 is a display, it is displayed on an image or text in which an obstacle exists in front of the host vehicle. Further, when the notification device 4 is a speaker, a voice message or a warning sound that an obstacle exists in front of the host vehicle is output.

  Furthermore, when the alerting | reporting apparatus 4 is a vibrator, the vibrator as the alerting | reporting apparatus 4 is vibrated with a predetermined vibration pattern, so that the driver is informed that an obstacle is present. The vibrator may be provided in a portion that contacts the driver's body, such as the driver's seat or handle. That is, the notification processing unit F6 performs the notification process in a manner corresponding to the notification device 4. Information indicating that there is an obstacle ahead of the host vehicle may be output in a manner that can be perceived by humans, such as image display, text display, light emission, vibration, and sound (including simple sounds).

  Conditions for the notification processing unit F6 to perform the notification processing may be appropriately designed. For example, the notification process may be performed when an obstacle exists within a certain distance from the ultrasonic sensor 2. When the obstacle determination unit F5 detects an obstacle, the notification process may be performed regardless of the distance between the obstacle and the ultrasonic sensor 2. In any case, the notification process may be performed based on the fact that the obstacle determination unit F5 detects an obstacle.

<Threshold adjustment processing>
Next, a series of processing (hereinafter, threshold determination processing) for the obstacle determination unit F5 to determine the noise influence threshold will be described using the flowchart shown in FIG. The flow chart shown in FIG. 6 may be executed sequentially (for example, every 100 milliseconds) when the vehicle is in a power supply state capable of traveling.

  First, in step S101, the image data acquisition unit F1 acquires image data generated by the camera 3, and proceeds to step S102. In step S102, the image recognition unit F2 performs image recognition processing using the image data acquired in step S101, thereby detecting various elements such as presence / absence of a change in road surface gradient, road surface condition, and weather condition. . When the process of step S102 is completed, the process proceeds to step S103.

  In the present embodiment, the image recognition process is performed for each frame taken by the camera 3, but the present invention is not limited to this. Image recognition processing may be performed using image data of a plurality of frames. For example, as a mode of generating a super-resolution image with improved resolution by using a well-known super-resolution technique based on image data for three consecutive frames, and detecting various elements from the super-resolution image Also good.

  In step S103, the image recognition unit F2 determines whether or not a noise element is present in the detection area of the ultrasonic sensor 2 as a result of the image recognition processing in step S102. If a noise element is detected in the detection area of the ultrasonic sensor 2, an affirmative determination is made in step S103 and the process proceeds to step S104. On the other hand, when a noise element is not detected in the detection area of the ultrasonic sensor 2, a negative determination is made in step S103, and the process proceeds to step S105.

  In step S104, the influence specifying unit F3 specifies the noise influence time zone. Then, the obstacle determination unit F5 generates the noise correspondence threshold ThN (T) used in the noise influence time zone based on the default threshold ThD (T), and ends this flow. In step S105, the default threshold value is adopted as the determination threshold value, and this flow ends.

<Summary of Embodiment>
In the above configuration, the obstacle determination unit F5 detects an obstacle using a default threshold when the image recognition unit F2 does not detect a noise element in the detection area of the ultrasonic sensor 2. On the other hand, when the image recognition unit F2 detects a noise element in the detection area of the ultrasonic sensor 2 and the elapsed time T corresponds to the noise influence time zone, the noise correspondence threshold is used. Detect obstacles.

  Therefore, for example, as shown in FIG. 7, even if there is a slope increasing point in front of the host vehicle, the reflected wave from the road surface extending farther than the slope increasing point returns. As the threshold value for determination of the time zone assumed to be, a noise corresponding threshold value ThN (T) larger than the default threshold value ThD (T) is applied. Therefore, it is possible to reduce the risk of erroneous determination that an obstacle exists due to a reflected wave from the road surface. Note that the broken line W1 in FIG. 7 conceptually represents the transition of the received intensity of the reflected wave from the road surface.

  In addition, as shown in FIG. 8, even when there is a minute step in front of the host vehicle, the default threshold for determining a time zone in which a reflected wave from the minute step is expected to return is the default. A noise correspondence threshold ThN (T) larger than the threshold ThD (T) is applied. Therefore, it is possible to reduce the risk of erroneous determination that an obstacle exists due to the reflected wave from the minute step. Note that the broken line W2 in FIG. 8 conceptually represents the transition of the reception intensity of the reflected wave from the minute step.

  That is, according to the above configuration, it is possible to reduce the risk of erroneous determination that an obstacle exists due to noise elements such as road surfaces and minute steps. As a result, the possibility that the notification processing unit F6 performs unnecessary notification can be reduced.

  Since the noise correspondence threshold is larger than the default threshold, using the noise mode threshold as the determination threshold corresponds to adopting a condition that is less likely to be satisfied as a condition for determining that an obstacle exists. . That is, in the embodiment described above, when a noise element is detected, whether or not an obstacle exists using a condition that is less likely to be satisfied than a condition used when the noise element is not detected. This corresponds to an example of a mode for determining whether or not.

  In the above configuration, when there is no noise element, the obstacle determination unit F5 determines the presence or absence of an obstacle using a default threshold. Further, even when there is a noise element, the obstacle determination unit F5 determines the presence or absence of an obstacle using a default threshold in a time zone that does not correspond to the noise influence time zone.

  Therefore, by setting the default threshold value to a relatively small value in advance, it is possible to detect the presence of an obstacle with a relatively high sensitivity in a situation that is not affected by the noise element. That is, according to the above configuration, it is possible to increase obstacle detection sensitivity while suppressing unnecessary notification.

  By the way, generally, the time zone corresponding to the region far from the ultrasonic sensor 2 tends to receive the reflected wave from the noise element with stronger reception intensity. This is because as the elapsed time from the transmission start timing increases, the ultrasonic pulse spreads and propagates through the space, and is reflected and returned by various elements.

  Therefore, as another mode for suppressing erroneous detection of obstacles due to noise elements and unnecessary notification, there is also a mode in which the default threshold is set to a larger value as the elapsed time becomes larger, as shown in FIG. Assumed (this is assumed configuration). In addition, the broken line W3 in FIG. 9 has shown the assumed value (henceforth an assumed noise level) of the receiving intensity of the reflected wave by a noise element according to elapsed time.

  However, in the assumed configuration, since the value increases as the distance from the ultrasonic sensor 2 increases, the detection sensitivity of an obstacle existing at a position away from the ultrasonic sensor 2 decreases. That is, if the default threshold is set to be larger than the assumed noise level, the range in which an obstacle can be detected becomes narrower in terms of software.

  In response to such a problem, in the configuration of the present embodiment, when a noise element exists, the determination threshold is changed and used so that erroneous detection of an obstacle by the noise element is suppressed. Therefore, according to the configuration of the present embodiment, the default threshold value of the time zone corresponding to the far region can be set to a value smaller than the assumed configuration. That is, a software-like (in other words, logical) detection area can be formed larger than the assumed configuration.

  In addition, although the aspect provided with the function of the obstruction determination part F5 in the periphery monitoring ECU1 was illustrated above, it is not restricted to this. The obstacle determination unit F5 may be provided in the ultrasonic sensor 2.

  Further, although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and the following embodiments and various modifications are also included in the technical scope of the present invention. In addition to the following, various modifications can be made without departing from the scope of the invention.

[Modification 1-1]
In the first embodiment, the default threshold after the reverberation convergence time Tx is set to a constant value. However, the present invention is not limited to this. Similar to the assumed configuration, the default threshold value may be set to a large value according to the elapsed time T from the transmission start timing.

  Even in such an aspect, the noise influence time zone is specified as in the first embodiment, and when the elapsed time T is the noise influence time zone, the noise correspondence threshold may be applied as the determination threshold. .

  For example, when the image recognition unit F2 detects a gradient increase point as a noise element as shown in FIG. 10, the influence specifying unit F3 specifies the noise influence time zone corresponding to the area where the noise element exists. To do. And the obstacle determination part F5 implements the presence or absence of an obstacle using the noise corresponding | compatible threshold value ThN (T) for using in a noise influence time slot | zone. In addition, the solid line in FIG. 10 represents the threshold value used for determination, and the broken line represents the default threshold value.

[Modification 1-2]
Further, in the above-described modified example 1, the noise influence time zone is specified, and a mode in which a value different from the default threshold ThD (T) is adopted as the determination threshold only in the noise influence time zone is disclosed, but the present invention is not limited thereto. Absent.

  The time zone other than the noise influence time zone is a time zone in which the possibility that a reflected wave from the noise element arrives is relatively low. Therefore, when the default threshold ThD (T) is set so as to exceed the assumed noise level, a value smaller than the default threshold ThD (T) is set as a threshold for determination in a time zone other than the noise affected time zone. It may be adopted to determine whether there is an obstacle.

  For example, as shown in FIG. 11, in the noise influence time zone, the noise suppression threshold is adopted as the determination threshold value, while in a time zone other than the noise influence time zone, a value lower than the default threshold ThD (T) is used. , Used as a threshold for determination. The value used as the determination threshold value in the time zone other than the noise influence time zone may be, for example, the uniform road surface assumed value Pc.

  FIG. 11 shows a case where a minute step is detected as a noise element, and a time zone from the elapsed time T3a to T3b is specified as the noise influence time zone. The elapsed time T3 represents the round trip flight time corresponding to the distance D3 from the ultrasonic sensor 2 to the minute step.

  According to such an aspect, even when the default threshold value is defined so as to increase with the elapsed time T, if it is not affected by the noise element, a smaller threshold value is used. The presence or absence of an object can be determined. That is, the range in which an obstacle can be detected can be expanded in software as compared with the first modification.

[Modification 1-3]
In 1st Embodiment, although the noise influence time slot | zone was identified and the aspect larger than a default threshold value was applied as a threshold value for determination of a noise influence time slot | zone, it was not restricted to this. For example, the noise correspondence threshold ThN (T) may be applied to all elapsed times after the reverberation convergence time Tx.

  Further, in addition to the above aspect, the noise correspondence threshold ThN (T) may be applied even in a time zone shorter than the reverberation convergence time Tx. That is, when the image recognition unit F2 detects a noise element, the noise correspondence threshold ThN (T) may be applied in all time zones. According to such an aspect, the process for specifying a noise influence time zone can be omitted.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings. In the following, members having the same functions as those of the first embodiment and the modifications thereof will be assigned the same reference numerals and explanation thereof will be omitted. In addition, when only a part of the configuration is mentioned, the first embodiment described above and its modifications can be applied to the other parts. The difference between the second embodiment and the first embodiment described above is the function provided in the periphery monitoring ECU 1. Below, the difference is mainly described.

  As shown in FIG. 12, the periphery monitoring ECU 1 in the second embodiment includes an image data acquisition unit F1, an image recognition unit F2, an exploration result acquisition unit F4, an obstacle determination unit F5, and a notification processing unit F6 as functional blocks. Is provided. The obstacle determination unit F5 includes a distance specifying unit F51 and a reflection detection unit F52 as finer functional blocks. The threshold storage unit M1 stores a default threshold ThD (T) corresponding to the elapsed time T from the transmission start timing.

  The reflection object detection unit F52 is a functional block that detects a reflection object that reflects an ultrasonic pulse based on the reception intensity provided from the search result acquisition unit F4. More specifically, the reflector detection unit F52 acquires the transmission start timing from the search result acquisition unit F4, and measures the elapsed time T from the transmission start timing. Then, when the currently input reception intensity exceeds the default threshold ThD (T) corresponding to the elapsed time T from the transmission start timing, it is determined that there is a reflector.

  The distance specifying unit F51 is based on the time required from the transmission start timing until the reflecting object detection unit F52 detects the reflecting object, in other words, the elapsed time T when the reflecting object detection unit F52 detects the reflecting object. Then, the distance to the detected reflector is specified. The specified distance is temporarily stored in the RAM 12.

  Then, the obstacle determination unit F5 determines that there is an obstacle when a reflection object is detected at a distance that can be regarded as the same distance continuously for a predetermined number of times. The number of determinations used here is changed depending on whether or not the image recognition unit F2 detects a noise element in the detection area of the ultrasonic sensor 2.

  For convenience, the fixed number of times adopted when the image recognition unit F2 has not detected a noise element in the detection area of the ultrasonic sensor 2 is the first fixed number of times, and the image recognition unit F2 has noise in the detection area of the ultrasonic sensor 2. The fixed number of times adopted when the element is detected is referred to as a second fixed number of times. The first determination number and the second determination number may be appropriately designed. Here, as an example, the first fixed number of times is 3 times and the second fixed number of times is 5 times. The second determined number may be a value larger than the first determined number. The first fixed number of times corresponds to the first prescribed number of times described in the claims, and the second fixed number of times corresponds to the second fixed number of times described in the claims.

  An outline of the operation of the periphery monitoring ECU 1 in the second embodiment will be described with reference to a flowchart shown in FIG. The flowchart shown in FIG. 13 may be executed sequentially (for example, every 100 milliseconds) when the vehicle is in a power supply state where the vehicle can run.

  The processing from step S201 to step S203 is the same as the processing from step S101 to step S103 in the flowchart shown in FIG. By the processing from step S201 to step S203, it is determined whether or not there is a noise element in the detection area of the ultrasonic sensor 2. If it is determined in step S203 that a noise element is present in the detection area of the ultrasonic sensor 2, an affirmative determination is made in step S203, and the process proceeds to step S204. On the other hand, when it is not determined that a noise element exists in the detection area of the ultrasonic sensor 2, a negative determination is made in step S203, and the process proceeds to step S205.

  In step S204, the obstacle determination unit F5 adopts the second fixed number as the fixed number of times, and ends this flow. On the other hand, in step S205, the first determination count is adopted as the determination count, and this float is finished.

  With the above configuration, when the image recognition unit F2 detects a noise element, the number of determinations used to determine that an obstacle is present is set to be larger than when no noise element is detected. In general, the reception intensity of a reflected wave from a noise element can be expected to vary every time an ultrasonic pulse is transmitted. Therefore, by increasing the number of determinations, it is possible to reduce the risk of determining that a noise element detected as a reflecting object is an obstacle. That is, according to the above configuration, the same effect as that of the first embodiment can be obtained.

  In addition, using the second fixed number of times larger than the first fixed number as the number of fixed times for determining that an obstacle is present means adopting a condition that is less likely to be satisfied as a condition for determining that an obstacle is present. It corresponds to doing. That is, in the second embodiment described above, when a noise element is detected, there is an obstacle using a condition that is less likely to be satisfied than a condition used when the noise element is not detected. This corresponds to an example of a mode for determining whether or not there is.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to the drawings. This third embodiment also includes a periphery monitoring ECU 1, an ultrasonic sensor 2, a camera 3, and a notification device 4, as in the above-described embodiments and modifications thereof. As shown in FIG. 14, the periphery monitoring ECU 1 in the present embodiment includes an image data acquisition unit F1, an image recognition unit F2, an exploration result acquisition unit F4, an obstacle determination unit F5, a notification processing unit F6, and an output as functional blocks. A level adjustment unit F7 is provided.

  The output level adjustment unit F7 changes the signal intensity (hereinafter, output level) of the ultrasonic pulse transmitted by the ultrasonic sensor 2. As a premise, the ultrasonic sensor 2 in the present embodiment has a configuration capable of adjusting the output level of the ultrasonic pulse.

  In the present embodiment, the ultrasonic sensor 2 has a configuration that can be set to two levels, that is, a preset rated level and a suppression level smaller than the rated level, as the output level of the ultrasonic pulse. And The suppression level only needs to be smaller than the rated level and may be appropriately designed. It is assumed that the ROM 13 stores data indicating the detection area when the output level of the ultrasonic sensor 2 is the rated level.

  The change of the output level may be realized by adjusting the driving voltage of the ultrasonic sensor 2. Further, the output level may be reduced by setting the frequency of the signal input to the oscillation element to a value shifted from the resonance frequency of the oscillation element by a certain amount (hereinafter referred to as suppression frequency). The suppression frequency is a frequency at which the output level becomes the suppression level.

  The operation of the output level adjustment unit F7 will be described with reference to the flowchart shown in FIG. The flowchart shown in FIG. 15 may be executed sequentially (for example, every 100 milliseconds) when the vehicle is in a power supply state where the vehicle can run.

  The processing from step S301 to step S303 is the same as the processing from step S101 to step S103 in the flowchart shown in FIG. By the processing from step S301 to step S303, it is determined whether or not a noise element exists in the detection area when the output level of the ultrasonic sensor 2 is the rated level. If it is determined in step S303 that a noise element is present, an affirmative determination is made in step S303, and the process proceeds to step S304. On the other hand, if it is not determined that a noise element is present in the detection area of the ultrasonic sensor 2, a negative determination is made in step S303, and the process proceeds to step S305.

  In step S304, the output level adjustment unit F7 sets the output level to the suppression level and ends this flow. On the other hand, in step S305, the output level is set to the rated level, and this flow ends.

  In the above configuration, when the image recognition unit F2 does not detect the noise element, the ultrasonic pulse is transmitted at the rated level. On the other hand, when the noise element is detected, the ultrasonic pulse is transmitted at the suppression level. Send it. Decreasing the output level corresponds to reducing the detection area of the ultrasonic sensor 2. That is, the obstacle notification system 100 according to the present embodiment makes the detection area smaller when the image recognition unit F2 detects a noise element than when a noise element is not detected.

  Naturally, if the detection area is reduced, the risk of erroneous determination that an obstacle exists due to noise elements such as a road surface after a slope increase point far from the host vehicle can be reduced. As a result, similar to the various embodiments and modifications described above, the risk of performing unnecessary notification processing can be reduced.

[Other variations]
In the above, an ultrasonic sensor is used as a sensor for detecting an obstacle existing around the host vehicle (hereinafter referred to as an obstacle sensor), but the present invention is not limited thereto. The obstacle sensor may be a millimeter wave radar that uses millimeter waves (including quasi-millimeter waves) as a search wave, a laser radar that uses light as a search wave, and the like. That is, the exploration wave transmission / reception device described in the claims may be a device other than the ultrasonic sensor, such as a millimeter wave radar or a laser radar.

DESCRIPTION OF SYMBOLS 100 Obstacle notification system, 1 Perimeter monitoring ECU (obstacle notification device), 2 Ultrasonic sensor (Exploration wave transmission / reception device), 3 Camera, 4 Notification device, 11 CPU, 12 RAM, 13 ROM, F1 Image data acquisition part, F2 Image recognition unit (noise element detection unit), F3 influence identification unit, F4 search result acquisition unit, F5 obstacle determination unit, F6 notification processing unit, F7 output level adjustment unit, F51 distance identification unit, F52 reflector detection unit, M1 Threshold storage unit

Claims (8)

Mounted on the vehicle,
Obtaining a search result that sequentially acquires the received intensity of the reflected wave received by the search wave transmitting / receiving device that transmits the search wave in the traveling direction of the vehicle and receives the reflected wave that is reflected back by the object. Part (F4),
Whether there is an obstacle in the traveling direction of the vehicle, which is an object that should be notified to the driver of the vehicle by using the received wave intensity of the reflected wave acquired by the exploration result acquisition unit An obstacle determination unit (F5) for determining
A notification processing unit (F6) that performs a notification process for notifying the driver of the presence of the obstacle based on the obstacle determination unit determining that the obstacle exists;
An image data acquisition unit (F1) that acquires image data captured by a camera that includes the reach of the exploration wave transmitted by the exploration wave transmitting / receiving apparatus in an imaging range;
By analyzing the image data acquired by the image data acquisition unit, it is an element that can reflect the exploration wave and is preset as an element that does not need to be notified to the driver A noise element detection unit (F2) for detecting the presence of a certain noise element,
When the noise element detection unit detects the noise element, the obstacle determination unit has a condition that is less likely to be satisfied than a condition used when the noise element detection unit does not detect the noise element. It is used to determine whether or not the obstacle is present. In claim 1,
The obstacle determination unit compares a threshold for determining whether or not the obstacle exists with the reception intensity of the reflected wave acquired by the search result acquisition unit, and receives the reflected wave Is determined to be present when the threshold is exceeded,
A default threshold is set in advance as the threshold to be used when the noise element detection unit does not detect the noise element,
The obstacle determination unit
When the noise element detection unit has not detected the noise element, while determining whether the obstacle exists using the default threshold,
Obstacle notification, wherein, when the noise element detection unit detects the noise element, it is determined whether or not the obstacle exists using a threshold value larger than the default threshold value. apparatus. In claim 2,
The default threshold value is set to a value according to the elapsed time after transmitting the exploration wave,
The noise element detection unit identifies a region where the noise element exists in the reachable range,
The obstacle determination unit
If the elapsed time after transmitting the exploration wave does not correspond to the time zone corresponding to the area where the noise element specified by the noise element detection unit exists, the default corresponding to the elapsed time While determining whether the obstacle exists using a threshold,
If the elapsed time after transmitting the exploration wave corresponds to the time zone corresponding to the area where the noise element specified by the noise element detection unit exists, the default corresponding to the elapsed time An obstacle notification device that determines whether or not the obstacle exists using a threshold value that is larger than the threshold value. In claim 3,
The obstacle determination unit
When the elapsed time after transmitting the exploration wave does not correspond to the time zone corresponding to the area where the noise element specified by the noise element detection unit exists,
Uniformity that is a value obtained by adding a predetermined margin to a value assumed as the reception intensity acquired by the search result acquisition unit in a situation where the slope of the road surface existing in the traveling direction of the vehicle is uniform. An obstacle notification device that determines whether or not the obstacle is present by using an estimated road surface value as the threshold value. In claim 3,
In the time zone after the time when reverberation accompanying the transmission of the exploration wave converges, the default threshold value is obtained when the degree of inclination of the road surface existing in the traveling direction of the vehicle is uniform. Is set to a uniform road surface assumed value obtained by adding a predetermined margin to the value assumed as the reception intensity acquired by the obstacle notification device. In any one of Claim 3 to 5,
As a time zone corresponding to the area where the noise element exists, the relative position with respect to the vehicle in the area where the noise element specified by the noise element detection unit and the installation position of the exploration wave transmission / reception device in the vehicle are determined. An obstacle notification device comprising an influence specifying unit (F3) for specifying a noise influence time zone, which is a time zone in which the reflected wave from the noise element returns. In claim 1,
The obstacle determination unit
An object that reflects the exploration wave based on the fact that the reception intensity of the reflected wave exceeds a threshold value for detecting the presence of the obstacle, which is preset with respect to the reception intensity of the reflected wave. A reflector detection unit (F52) for detecting the presence of a reflector;
Based on the time required from transmitting the exploration wave to receiving the reflected wave corresponding to the reflection object, the distance from the exploration wave transmission / reception device to the reflection object detected by the reflection object detection unit is calculated. A distance specifying unit (F51) for specifying,
In the case where the noise element detection unit does not detect the noise element, the reflection object detection unit detects the reflection object at a distance that can be regarded as the same distance continuously for a predetermined first specified number of times. While determining that the obstacle exists,
When the noise element detection unit detects the noise element, the reflector detection unit has a distance that can be regarded as the same distance continuously for a second specified number of times that is greater than the first specified number of times. An obstacle notification device that determines that the obstacle is present when the reflector is detected. Mounted on the vehicle,
Obtaining a search result that sequentially acquires the received intensity of the reflected wave received by the search wave transmitting / receiving device that transmits the search wave in the traveling direction of the vehicle and receives the reflected wave that is reflected back by the object. Part (F4),
In comparison with a default threshold value that is set in advance to determine that there is an obstacle that should be notified to the driver of the vehicle, the received intensity of the reflected wave acquired by the search result acquisition unit, An obstacle determination unit (F5) that determines that the obstacle exists when a reflected wave exceeds the default threshold;
A notification processing unit (F6) that performs notification processing for notifying the driver of the presence of the obstacle based on the obstacle determination unit determining that the obstacle is present;
An image data acquisition unit (F1) that acquires image data captured by a camera that includes the reach of the exploration wave transmitted by the exploration wave transmitting / receiving apparatus in an imaging range;
By analyzing the image data acquired by the image data acquisition unit, it is an element that can reflect the exploration wave and is preset as an element that does not need to be notified to the driver A noise element detector (F2) for detecting the presence of a noise element;
When the noise element detection unit detects the noise element, the output level of the exploration wave is preset as an output level used when the noise element detection unit does not detect the noise element. An output level adjustment unit (F7) for adjusting to a level smaller than the rated level,
The obstacle wave notification device, wherein the exploration wave transmission / reception device transmits the exploration wave at an output level set by the output level adjustment unit.

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